1. Field of the Invention
The present invention relates to network management and, more particularly, to a method and apparatus for provisioning optical services on an optical network.
2. Description of the Related Art
Data communication networks may include various routers, switches, bridges, hubs, and other network devices coupled to and configured to pass data to one another. These devices will be referred to herein as “network elements.” Data is communicated through the data communication network by passing protocol data units, such as Internet Protocol (IP) packets, Ethernet frames, data cells, segments, or other logical associations of bits/bytes of data, between the network elements by utilizing one or more communication links between the devices. A particular protocol data unit may be handled by multiple network elements and cross multiple communication links as it travels between its source and its destination over the network.
In optical networks, the connections between the elements must be provisioned to enable data to be passed over the optical network. The connections are statically provisioned through the network so that a particular service instance will be connected between ports on network elements and remain provisioned over those ports until the provisioning is changed or shut down. For example, once the optical network elements are interconnected by optical fibers, a network manager will log into an optical service provisioning system to set up data connections (services) through the network elements and optical fibers. Examples of commonly offered services include T1, T3, etc.
Conventionally, provisioning of services has been done manually on a work-order basis. Specifically, when a new service is to be provisioned, the network manager will log into the optical service provisioning system to define the network resources that are to be used to implement the service. Although automatic provisioning systems have been created, due to the complexity of connection options, service providers tend to prefer the manual method of provisioning services due to the increased ability to control the manner in which the services are created.
Optical connection management is quite complex, due to the different ways in which a service may be created on the optical network. For example, a given service may require path and line protection, concatenation of services, and layering of services. Since optical services are offered in blocks of bandwidth of a particular size (channels), it is often necessary to concatenate several channels together to build a service of the desired bandwidth. Since these concatenated channels may be physically carried on different paths through the network, the manner in which they are protected may be different for each concatenated block of bandwidth. Additionally, the underlying transport mechanisms may be different which also complicates the manner in which a service must be provisioned.
To address these issues, optical service provisioning systems have been developed that enable a network manager to specify how a service should be specified between network elements and within a given network element. Unfortunately, the optical service provisioning systems require extensive training and require the network manager to remember a significant amount of information. Thus, it is not uncommon for it to take an experienced network manager about 30 minutes to set up one backbone connection using existing optical provisioning systems.
Several factors contribute to the complexities associated with optical provisioning. For example, the vendors that design optical networking equipment haven't agreed on a standard to be used for topology discovery, and there generally is limited proprietary auto-discovery. Thus, discovery of the network topology in a network created using network elements from multiple vendors creates gaps in the system knowledge, resulting in visualization of the network that is limited at best. These gaps in topology were generally required to be input using a topology program which was separate from the optical provisioning system. Since the two systems were separate, the network manager would need to stop provisioning the service, cause the topology to be entered, and then continue the provisioning process.
Additionally, the network elements typically only store nodal connection data so that the information that is available generally is associated with connections through a particular node, rather than paths across the network. Specifically, the network elements themselves only know that a connection on one input port is routed out through another output port. The nodal data stored by the network element for the connection frequently may be quite limited, for example including a 40 character connection ID. Since services are typically based on end-to-end connections or collections of such connections, the nodal data is of limited value to tracing existing connections through the network. While systems exist that will allow a single path to be derived by walking a series of nodal connections and topology, these systems are limited in many ways. Specifically, in their ability to deal with the concept of several individual paths being concatenated to form one service, in dealing with gaps in topological information, and in the manner in which they described these derived path(s).
In addition to the limitations associated with knowledge of the underlying network, the network manager must also contend with the complexities of describing the service that is to be created on the network. For example, a given nodal connection may need different combinations of protection, concatenation, and routing functions. The complex functions also require a large number of termination points to be specified. Even without concatenation, the number of connection types may be quire large and is continuing to increase. Existing terminology and user interface designs are concomitantly complex and either require the network manager to remember a large number of acronyms for the particular connection type to be established through the network element, or require the network manager to use multiple clicks to extract the correct connection from the user interface.
Finally, within a network element it may be difficult to select the correct port or ports to handle the connection. Port naming is relatively complex, which may make it difficult to identify the correct port or ports for an intended service. Additionally, when selecting between ports, the destination of the service may constrain the port selection process since only particular ports may connect to a given destination. Since the nodes may not know which port is connected to a particular destination, selecting the proper port may be difficult. Additionally, once a port is selected, one or more levels of channel selection within the port may need to be specified as well. Where the port does not have sufficient channels to support an intended connection, the channel selection process may require a new port selection to occur. Additionally, different customers use different modes of operation which further makes it difficult to implement port selection using existing user interfaces.
Accordingly, it would be advantageous to provide a method and apparatus for provisioning optical services on an optical network that may be able to improve on one or more of these deficiencies in current optical provisioning systems.